Upset forging machines



Jan. 11, 1966 H. F. ETCHELLS UPSET FORGING MACHINES 3 Sheets-Sheet 1 Filed Aug. 12, 1963 4A WW Jan. 11, 1966 H. F. ETCHELLS 3,228,229

UPSET FORGING MACHINES Filed Aug. 12, 1963 3 Sheets-Sheet 2 INVENTOR: ET M W Jan. 11, 1966 H. F. ETCHELLS 3,228,229

UPSET FORGING MACHINES Filed Aug. 12, 1963 3 Sheets-Sheet 5 INVENTOR: *Wmi QWMW+PW United States Patent 3,228,229 UPSET FORGING MACHINES Henry F. Etchells, Wolverhampton, England, assignor to David Etchells (Machinery) Limited, Stafiordshire, England Filed Aug. 12, 1963, Ser. No. 301,570 Claims priority, application Great Britain, Aug. 22, 1962, 32,182/62 3 Claims. (Cl. 72-451) This invention relates to upset forging machines of the kind in which the or each workpiece to be operated upon by a reciprocated upsetting tool is held between a stationarily fixed locating tool and a relatively movable gripping tool, which latter is mounted on a slide which is operated by toggle and link mechanisms, the arrangement being such that the or each workpiece remains held during the heading or other upsetting operation and is then released for removal and substitution by a fresh workpiece during the withdrawal of the said upsetting tool ready for the next forging stroke.

The object of the invention is to provide upset forging machines of the kind referred to with an overload or safety device which will prevent damage to the machine in the event of the gripping tool on the toggleoperated slide being positively obstructed from closing upon the fixed locating tool. A further object of the invention is to provide in association with said safety device means which will enable the gripping tool slide to be held in an out-of-way position well clear of the fixed locating tool and prevented from operation during tool setting or adjusting operations.

The invention will now be described with reference to the accompanying drawings, in which:

FIG. 1 is a side elevation of an upset forging machine of the kind first herein referred to.

FIG. 2 is a side elevation of the mechanism for operating the upsetting tool and the gripping tool slide, the parts being shown in the positions they occupy in FIG. 1.

FIG. 3 is a similar view to FIG. 2 but illustrates the gripping tool slide held against operation in its fully raised position for tool setting or adjustments to be carried out.

FIG. 4 is a rear elevation of FIG. 2.

Referring to the drawings, and particularly to FIG. 1, is the machine frame, 11 is a slide mounted for horizontally guided movement therein, 12 is the stationarily fixed locating tool for supporting the workpiece in front of the upsetting or heading tool 13 carried by the slide 11, and 14 is a relatively movable top tool for gripping or holding down the workpiece upon the locating tool 12, said top or gripping tool 14 being carried by a slide 15 which is guided for vertical movement in the machine frame and is operable by a toggle 16. The upsetting tool slide 11 is reciprocated by a crank 17 and connecting rod or pitman 18 from a main shaft 19 which is driven in rotation by a motor 20 through a pulley 21, endless belt 22 and flywheel pulley 23, and said connecting rod or pitman 18 is connected by a rearwardly extending pivotal link 24 to the lower end of an actuating lever 25 which is pivotally mounted upon a rockshaft 26.

A main link 27 which operates to make and break the toggle 16, whereby the gripping tool slide 15 is operated, is connected to the upper end of the actuating lever 25 by an auixiliary pivotal link 28 which is normally almost in line with said toggle operating or main link 27 (as indicated by the respective centre lines in FIG. 2) but is prevented from passing through a dead centre position by an abutment 29 which is carried by and fixed between laterally spaced limbs of the rear end portion of said main link 27 and bears down upon the pivot which connects the auxiliary link 28 to the actuating lever 25.

A double acting fluid pressure cylinder 30 and piston 31, constituting a third link which is variable in effective length, connects the auxiliary link 28 to a point on the main link 27 forwardly of the pivotal connection between said auxiliary link 28 with the actuating lever 25.

The arrangement is such that under normal operating conditions each workpiece to be operated upon is held between the locating tool 12 and gripping tool 14 during the upsetting operation by the tool 13 and is then released for removal and substitution by" a fresh workpiece during the withdrawal of said tool 13 ready for the next operation. In this connection as the crank 17 approaches and passes through the rear dead oentre position in reversing the motion of the slide 11 the link 24 turns about its pivotal connection with the actuating lever 25 without imparting rocking movement thereto, thereby ensuring a dwell after each upsetting or heading stroke, during which dwell the actuating lever 25 is stationary and the gripping tool slide 15 remains fully raised to permit changing of the workpieces. Alternatively the actuating lever 25 may be operated by a rotary cam keyed to the crank shaft, said cam being profiled to afford the requisite dwell.

In the event of an obstruction preventing the gripping tool 14 on the toggle-operated slide 15 from closing upon the locating tool 12, the continued movement of the actuating lever 25 causes the auxiliary link 28 to turn about its pivotal connection with the main link 27 and the latter merely to pivot about its pivotal connection with the toggle 15 without any operative effect thereon, thereby relieving the mechanism from overload and preventing damage thereto.

If the gripping tool slide 15 is not in its fully raised or withdrawn position when the machine is stopped, either for removal of an obstruction or for tool resetting or adjustment, the auxiliary link 28 can be operated independently of the actuating lever 25 by appropriate pressurisation of the cylinder 30 to bring the tool slide 15 into the fully raised or withdrawn position. Reverse pressurisation of said cylinder 30 will return the auxiliary link 28 to its normal position, as determined by the abutment or stop 29, ready for normal operation during which operation the auxiliary lever 28, being at only a small angle to the main link 27, serves as a strut or stay between the actuating lever 25 and the main link 27 to impart reciprocation to the latter in accordance with the intermittent oscillation of said actuating lever 25. If when the machine is stopped the tool slide 15 is in its fully raised position appropriate pressurisation of the cylinder will ensure that it is maintained in that position whilst an obstruction is cleared.

Having fully described my invention, what I claim and desire to secure by Letters Patent is:

1. An upset forging machine of the kind having a fixed locating tool and a gripping tool slide, said forging machine comprising a toggle connected to said gripping tool slide, a main link which operates to make and break said toggle whereby the gripping tool slide is operated, an acuating lever, said lever being connected to said main link by an auxiliary pivotal link which normally is almost in line with said main link but is prevented from passing through a dead centre position so that, in the event of an obstruction preventing the gripping tool on the gripping tool slide from closing upon the fixed locating tool, continued movement of the actuating lever causes the auxiliary link to turn about its pivotal connection with the main link and the latter merely to pivot about its pivotal connection with the toggle without any operative effect thereon, thereby relieving the mechanism from overload and preventing damage thereto.

2. An upset forging machine as claimed in claim 1, including a third pivotal link interposed between the auxiliary pivotal link and the main link, said third pivotal link including a double-acting fluid pressure cylinder and piston for adjusting the effective length of the third link, the arrangement being such that the said cylinder can be pressurised to turn the auxiliary link about its pivotal connection with the main link to enable relative movement to take place between the actuating lever and the main link by pivotal movement of the auxiliary pivotal link.

3. An upset forging machine as claimed in claim 2,

wherein when the machine is stopped and with the grip- 15 ping tool slide is in its fully withdrawn position, appropriate pressurisation of the cylinder will lock the auxiliary pivotal link, the actuating lever and the main link into a rigid assemby to hold the tool slide in said fully withdrawn position.

References Cited by the Examiner UNITED STATES PATENTS 1,300,240 4/1919 Blakeslee 1023 1,313,345 8/1919. Smith 78---17 1,382,625 6/1921 Clouse lO--23 1,786,006 12/1930 Criley 74-585 1,975,537 10/1934 Criley l0-23 CHARLES W. LANHAM, Primary Examiner.

WILLIAM J. STEPHENSON, Examiner. 

1. AN UPSET FORGING MACHINE OF THE KIND HAVING A FIXED LOCATING TOOL AND A GRIPPING TOOL SLIDE, SAID FORGING MACHINE COMPRISING A TOGGLE CONNECTED TO SAID GRIPPING TOOL SLIDE, A MAIN LINK WHICH OPERATES TO MAKE AND BREAK SAID TOGGLE WHEREBY THE GRIPPING TOOL SLIDE IS OPERATED, AN ACUATING LEVER, SAID LEVER BEING CONNECTED TO SAID MAIN LINK BY AN AUXILIARY PIVOTAL LINK WHICH NORMALLY IS ALMOST IN LINE WITH SAID MAIN LINK BUT IS PREVENTED FROM PASSING THROUGH A DEAD CENTRE POSITION SO THAT, IN THE EVENT OF AN OBSTRUCTION PREVENTING THE GRIPPING TOOL ON THE GRIPPING TOOL SLIDE FROM CLOSING UPON THE FIXED LOCATING TOOL, CONTINUED MOVEMENT OF THE ACTUATING LEVER CAUSES THE AUXILIARY LINK TO TURN ABOUT ITS PIVOTAL CONNECTION WITH THE MAIN LINK AND THE LATTER MERELY TO PIVOT ABOUT ITS PIVOTAL CONNECTION WITH THE TOGGLE WITHOUT ANY OPERATIVE EFFECT THEREON, THEREBY RELIEVING THE MECHANISM FROM OVERLOAD AND PREVENTING DAMAGE THERETO. 